Method for protecting organic material against the degradative effects of ultra-viole light radiation



United States Patent '0 METHOD FOR PROTECTING ORGANIC MATE- RIAL AGAINSTTHE DEGRADATIVE EFFECTS OF ULTRA-VIOLET LIGHT RADIATION Albert F.Strobe], Delmar, and Sigmund C. Catino, Castleton, N.Y., assignors toGAF Corporation, a corporation of Delaware No Drawing.Continuation-impart of application Ser. No. 97,758, Mar. 23, 1961. Thisapplication June 23, 1965, Ser. No. 466,411

14 Claims. (Cl. 106-176) ABSTRACT OF THE DISCLOSURE A method forprotecting organic material against the degradative effects ofultra-violet radiation which comprises incorporating into said organicmaterial an essentral-ly colorless compound of the formula COORconsisting of alkylene, substituted alkylene, arylene, substitutedarylene, and bi-substituted heterocyclic radicals.

This application is a continuation-in-part of co-pending applicationSerial No. 97,758, filed Mar. 23, 1961, and now abandoned.

This invention relates to new and useful compositions which arecharacterized as having superior resistance to degradation anddeterioration when exposed to actinic radiation and in particular toorganic compositions which are protected against deterioration whenexposed to such radiations by the incorporation therewith of2-alkoxyu-cyano-l-naphthaleneacrylic esters. This invention furtherrelates to processes for preventing the deterioration and degenerationof organic materials when exposed to actinic radiations, and inparticular to ultra-violet radiations. This invention still furtherrelates to processes for the stabilization against deterioration byultra-violet light of organic materials by the use of2-alkoxy-a-cyano-1- naphthaleneacrylic esters.

Various organic compounds exhibit the power to absorb electromagneticradiations Within the band of 2900 to 3700 A. and when incorporated invarious plastic materials such as transparent sheets, the resultantsheet acts as a filter for all of the radiation passing through and willtransmit only such radiations as are not absorbed by the sheet and/orthe absorbing agent. It is thus possible to screen out undesirableradiations and utilize the resulting transparent sheet as a filter inmany technical and commercial applications such as wrappings for foodproducts and the like.

Numerous organic compounds have been suggested as absorbents for therange of radiations described above, which range is designated as theultra-violet range. Such "ice uses include incorporation in plasticsheet materials and the stabilization in general of transparent plasticbodies. By far, the greatest concern with respect to ultra-violetradiations is with those radiations which come from the sun. Most ofthese radiations have wave lengths between 250 and 400 millimicrons. Theeffects of such radiation on the human skin, producing sunburn andsuntan, are of course well known. Other effects, however, of greatcommercial importance relate to the photochemical degradation caused byultra-violet radiations. Many commercial products are either unstablewhen subjected to such radiations, or are affected to the extent thatthey become undesirable or unsalable. Many plastic "materials, whenexposed to this radiation, undergo substantial degradation resulting inthe development of undesirable color bodies and subsequent loss oftransparency. Food products, in addition to becoming discolored, oftenbecome unfit for human consumption. Thus, prolonged exposure of fruits,edible oils, butter and other prepared foods will spoil and turn rancidon exposure to ultra-violet light. It is well known that colored objectssuch as dyed textiles will fade on exposure to sunlight, and inparticular to ultra-violet light. Many plastics, in addition todeveloping color formation and reduction in transparency, becomebrittle, lose their elasticity, crack and eventually completelydeteriorate on exposure to sunlight. Paints, varnishes, lacquers and thelike also are prone to these effects, even though here the transparencyproperty may not be paramount.

We have discovered that by combining2-alkoxy-acyano-l-naphthaleneacrylic esters with organic materials,there results compatible combinations with a vast number of film formingplastics, resins, gums, waxes and the like, which combinations furtherexhibit outstanding ultraviolet absorbing properties within thegenerally encountered ultra-violet region of 250 to 400 millimicrons.The compounds which are employed in the compositions and processes ofthis invention, even though they exhibit outstanding absorbingproperties close to the visible region of the electro-magnetic field,nevertheless are essentially colorless compounds and can be employedwith the assurance that they will not contribute to color in normallycolorless formulations, nor will they affect the color of a coloredformulation such as a paint film or a dyed textile. Many of thecompounds employed in the compositions and processes of this inventionalso absorb some visible light on the violet end of the spectrum whichrenders them particularly useful in many formulations which aresusceptible to visible light degradation. Thus polyesters andpolyethylene are known to be so characterized, and the stabilization ofthese materials is extremely successful when using the compounds hereincontemplated.

It is therefore an object of the present invention tc provide new anduseful compositions characterized by improved resistance to degradationand deterioration by ultra-violet radiation.

It is still another object of this invention to provide compositionscontaining 2-alkoxy-u-cyano-1-naphthaleneacrylic esters which areresistant to ultra-violet deterioration.

It is a still further object of this invention to provide processes forimproving the resistance of organic materials to deterioration anddegradation by actinic radiatior and especially ultra-violet radiation.

It is a still further object of this invention to provide compositionsand processes for improving the resistanc: of organic materials todeterioration and degradation by actinic radiations including short wavelength visible radi ations.

Other objects and advantages will appear hereinafte as the descriptionproceeds.

a 9 The 2 alkoxy L cyano 1 naphthaleneacrylic esters nich are employedin the compositions and processes this invention are characterized bythe following genal formula:

/\ OR \COORZ K (1) herein R is a lower alkyl of from 1 to 9 carbon atomslower alkenyl radical of from 3 to 9 carbon atoms, for example, methyl,ethyl, propyl, isopropyl, butyl, )butyl, amyl, hexyl, heptyl, octyl,nonyl, allyl and the 1e, and R is alkyl, hydroxyalkyl, haloalkyl,cyanoalkyl, soxyalkyl, hydroxyalkoxyalkyl, carbalkoxyalkyl, alke- 'l,aryl, substituted aryl, hetero and the like.

The carbon atom content of the alkyl and alkenyl oieties of R is notcritical and may vary from 1 to out 30. The same limitation applies aswell to the umerated substituted forms. The substituted aryl moies, asillustrated below, contain the usual non-chromo- .oric substituents suchas alkyl, alkoxy, halogen, car- Xy, carboalkoxy, acylamino,alkylsulfonyl, cyano, and a like. Chrornophores are to be avoided,obviously, ice the compounds used in this invention must be colors orsubstantially so. Groups to be specifically avoided azo and nitro, aswell as amino groups bonded directly the naphthalene ring.

The following specific substituents for R may be em- )yed in the abovegeneric formulation: methyl, ethyl, oropyl, iso-propyl, n-butyl,iso-butyl, n-amyl, iso-amyl, Xyl, heptyl, nonyl, decyl, undecyl, lauryl,tetradecyl, aryl, and the like, propenyl, iso-propenyl, allyl, l-butel,2-butenyl, 3-butenyl, l-methylpropenyl, l-pentenyl, nethyl-l-butenyl,hexenyl, heptenyl, octenyl, nonenyl, cenyl, undecenyl, oleyl,tetradecenyl, hexadecenyl, octa- :enyl, cyanoethyl, cyanopropyl(N-propyl, isopropyl), anobutyl (N-butyl, isobutyl, etc.), cyanoamyl,cyanoxyl, cyanooctyl, cyanononyl, cyanodecyl, cyanoundecyl, anolauryl,and the like, hydroxyethyl, hydroxypropyl l-propyl, isopropyl),hydroxybutyl (N-butyl, isobutyl, hydroxyamyl, hydroxyhexyl,hydroxydecyl, hy- Jxylauryl, and the like, chloroethyl, chloropropyl (N-)pyl, isopropyl), chlorobutyl (N-butyl, isobutyl, etc.), loroamyl,chlorohexyl, chlorodecyl, chlorolauryl, and a like, bromoethyl,bromopropyl (N-propyl, isopropyl), omobutyl (N-butyl, isobutyl, etc.),bromoamyl, bromoxyl, bromodecyl, bromolauryl, and the like, methoXyryl,methoxypropyl (N-propyl, isopropyl), methoxytyl (N-butyl, isobutyl,etc.), methoxyamyl, methoxyxyl, methoxydecyl, methoxylauryl, and thelike, loxyethyl, ethoxypropyl (N-propyl, isopropyl), ethoxytyl (N-butyl,isobutyl, etc.), ethoxyamyl, ethoxyhexyl, ioxydecyl, ethoxylauryl, andthe like, polyhydroxyiyls, e.g., glycaryl.

Heterocyclics: furyl, tetrahydrofurfuryl, benzofuryl, ienyl, pyrryl,pyrollidyl, 2-pyrollidonyl, indolyl, carzolyl, oxazolyl, thiazolyl,pyrazolyl, pyridyl, pyrimidyl, liIlOlYl, and the various alkyl, alkoxy,halo, carboxy, rboxalkoxy, acyl, and acylamino derivatives of theorementioned heretocyclic radicals.

Aryls: phenyl, tat-naphthyl, ,B-naphthyl, a-anthracyl, anthracyl,v-anthracyl, cumyl, phenanthranyl, anisole, tenetole, tolyl,p-diethoxyphenyl, l-methoxy phenan ryl, B-naphthyl methyl ether,fi-naphthyl ethyl ether, 'droxyethyl phenyl, hydroxypropyl phenyl,p-hydroxyhyl naphthyl, chlorophenyl, bromophenyl, 1,2-dichlorolCIlYl,1,3-dichlorophenyl, 1,3,5-trichlorophenyl, 1,2-diomophenyl,o-chlorotolyl, m-chlorotolyl, m-bromotolyl, omo-o-xylyl, a,B-dichloronaphthyl, 4-bromoacenaphyl, methylsulfonylphenyl, ethylsulfonylphenyl,cyanoienyl, cyanonaphthyl, carboxyphenyl, carboxytolyls, trboxyxylyls,carbalkoxyphenyls, e.g., carbomethoxylphenyl, carboethoxylphenyl,carbalkoxytolyls, e.g., carbomethoxytolyls, 'acetophenyl, propiophenyl,butyrophenyl, lauroylphenyl, p-acetotolyl, benzoyl naphthyl,acetaminophenyl, acet-methylamino phenyl, acetoaminotolyls,acetoaminonaphthyls, propio aminophenyl, propio aminotolyls.

In addition, R may represent a substituent of the formula: 1

wherein X is formula (I) devoid of the R substituent and R is abridging'group which may be alkylene, substituted alkylene,. arylene,substituted arylene or heterocyclic, e.g.,

I /CH3 @cmombn-om- I CH, 01120112011,-

CH H -cm thereby giving rise to bis-products of the formula:

CN NC wherein R and R have the meanings designated above.

The general process for the preparation of the compounds of Formula Iinvolves the condensation of a 2- alkoxy-l-naphthaldehyde with ana-cyano-acetic ester in the presence of an amine catalyst as describedin copending application Ser. No. 13,720 filed Mar. 9, 1960, now U.S.Patent 3,085,097.

As described in said aforementioned application the usual procedureinvolves heating a mixture of the reactants in the presence of the basiccatalyst at elevated temperatures until the reaction has gone tocompletion. A solvent may be employed to effect miscibility of thereactants and when such a solvent is used, the temperature of thereaction will usually be the reflux temperature of the solvent solutionof the ingredients. Ethyl alcohol is the preferred solvent in suchreaction. In the absence of a solvent, temperatures of the order of 75to 150 C. may be used. The time of reaction will of course varydepending upon the specific reactants and the temperature used. In someinstances a relatively low temperature for a short period of timeeffects the formation of a substantially quantitative yield of thedesired ester. In other cases, longer times and higher temperatures arenecessary to get the best yields. It is of course again obvious to oneskilled in the art to ascertain for any given combination of reactantsthe most eificacious combination of temperature and time. Upon thecompletion of the esterification reaction, the desired ester isisolated, usually by evaporation of the volatile constituents, namely,Water which is liberated in the condensation reaction, any alcohol whichmay be employed as a solvent, and the basic catalyst where the latter isa liquid and normally and readily removable by distillation orvolatilization. It is also possible in certain instances, to isolate thedesired ester product by diluting the reaction mixture with a solventwhich precipitates out the ester. Thus, methanol may be employed in manycases as such a diluent, and the resultant slurry is then filtered atlow temperatures (0 to 5 C.) to separate the crystalline product.

f The compounds of the general Formula II above are prepared in asimilar manner except that instead of employing cyanoacetic acidderivatives containing a single active methylene grouping, one employs apolycyanoacetate of a polyhydric alcohol using 2 moles of the aldehydefor each mole of the polycyanoacetate, thereby giving rise to the bestcompounds of Formula II. The polycyanoacetates are, of course, firstprepared, and usually in the manner described in US. Patent 2,426,056,from the corresponding polyhydric alcohol and cyanoacetic acid in thepresence of an acidic catalyst.

Formulae I and II may be generically represented by the followinggeneral formula:

wherein R and R are as designated above in Formula I and additionally Rmay be the same as R in Formula II and n is the integer 1 or 2; whenn=l, R is as in Formula I and when 11:2, R is as defined in Formula II.v V

In addition to the above contemplated derivatives, further compoundswhich are within the purview of this invention are the polyoxyalkylatedcompounds derived from reactive hydrogen containing compounds, i.e., inthe instant case, hydroxy compounds and an alkylene oxide or a compoundfunctioning as an alkylene oxide such as ethylene oxide, propyleneoxide, butylene oxide, butylene dioxide, cyclohexane oxide,epichlorohydrin, butadiene dioxide, isobutylene oxide, styrene oxide,mixtures thereof and the like.

The following examples will serve to illustrate the present inventionwithout being deemed limitative thereof. Unless otherwise indicated,parts are by weight.

Example 1 Preparation of a-cyano2-ethoxy-l-naphthaleneacrylic acid,ethyl ester:

COOCgHs --OCgH5 A mixture of 74 g. (0.37 mole)2-ethoxy-l-naphthaldehyde, 41.8 g. (0.37 mole) a-cyanoethyl acetate, and0.85 g. (0.01 mole) piperidine is stirred 1 hour at 95 C. The reactionmixture is allowed to cool to 60 C. and diluted with 120 mls. methanol.The slurry is filtered at 3 C to separate the crystalline product. Thefilter cake is washed with mls. methanol and air dried at room ternperature. The yield is 102 gms. of material of MP. 70- 78 C., whichcorresponds to a yield of about Example 2 Application of ester ofExample 1: Incorporation of this material into cellulose acetate iscarried out as follows:

0.375 gm. a-cyano-2-ethoxy-l-naphthaleneacrylic acid ethyl ester, 3.5gms. ethanol, 6.5 gms. methyl Cello solve, 9.0 gms. ethyl acetate, 26gms. cellulose acetate dope (consisting of 3.75 gms. cellulose acetatein 21 gms. acetone) are mixed with stirring until a clear solution isobtained The material is poured into a mold and the solvent evap oratedto give a block of cast material of A5" thickness A similar block isprepared in the same fashion only omit ting the naphthaleneacrylic acidderivative. The cast ma terial containing the ultra-violet absorbergives better sta bility to light to food materials stored behind it thanthe cast block without the ultra-violet absorber.

Example 3 Preparation of COOCHs -OCH3 Example 4 A composition comprisingthe following ingredients is epared:

% cellulose acetate (pulverized) 75% triphenyl phosphate .6% methylCellosolve .8% ethyl acetate -.3% ethyl alcohol The above components areadded in the above order id rolled until the cellulose acetatedissolved. 50 gms. the dope is weighed out and 0.05 gm. of the absorberExample 5 then added and dissolved. (Approximately of total solids.)Films are cast from these solutions I a clean glass plate using a doctorblade with a 6 mil ening to obtain a dry film approximately 6 milsthick. control film without ultra-violet absorber is also prered forcomparison.

The film containing ultra-violet absorber shows defitely betterprotection of foods stored behind it upon posure to light than the filmwithout the ultra-violet sorbet.

first prepared:

'0 gms. (2 moles) of cyanoacetic acid is mixed with .2 gms. (2.2 moles)of tetrahydrofurfuryl alcohol, 300 ls. chloroform, and 10 gms. of amixed alkane sulnic acid catalyst in a 1-liter flask equipped withconnser and water separator. The material is heated unlr reflux on asteam bath until no more water is taken E. The product is treated with(wt/vol.) sodium 'd'roxide and washed until neutral to delta paper. Theoduct is extracted with chloroform, dried, solvent reoved, and distilledat 140-144 C. at 0.5 mm. Yield: 1%. This intermediate (0.37 mole) isthen condensed .th 0.37 mole of 2-ethoxy-1-naphthaldehyde in the folwingmanner: A mixture of 0.37 mole of the aldehyde, ld 0.37 mole of theintermediate above prepared, with 01 mole of piperidine is stirred for 1hour at 95 C. re reaction mixture is then allowed to cool to 60 C. 1ddiluted with 120 mls. of methanol. A slurry is pro- 8 duced, whichslurry is filtered at 3 C. to separate the crystalline product. Thefilter cake is then washed with 100 mls. of methanol and air dried atroom temperature.

Example 6 The product of Example 5 is applied to polyethylene asfollows:

0.5 gm. ultra-violet absorber of Example 5 99.5 gms. polyethylene wax PT95504 (semet-solvay) are melted at 120 C. to give a solution. Thematerial is then pressed out in a Carver press to give a film of about/s in. thickness. Meat stored behind the film containing absorber isless discolored on exposure to light than meat stored behind similarfilm prepared without absorber.

Example 7 Preparation of:

7 /CN HC=C\ COOCgH The intermediate 2-allyloxy-1-naphthaldehyde is firstprepared according to the following reaction:

A mixture of 12 gms. Z-hy-droxy-l-naphthaldehyde (0.07 mole), 4 gms.potassium, mls. alcohol, and 15 gms. allyl bromide (0.14 ml.) isrefluxed 5 hours. The precipitate of potassium bromide is filtered, andthe alcohol and excess ally] bromide is distilled from the filtrate. Theresidue 'from distillation is treated with sodium hydroxide solution toseparate unchanged naphthaldehyde. The residue is further washed withwater to give a substantially pure residue of2-allyloxy-l-naphthaldehyde.

The 2-allyloxy-1-naphthaldehyde is then condensed with u-cyanoethylacetate in the following manner. A mixture of 0.37 mole of thenaphthaldehyde, 0.37 mole of a-cyanoethyl acetate, and 0.01 :molepiperidine is stirred for 75 min. at C. The reaction mixture is thenallowed to cool to about 60 C. and then diluted with mls. methanol. Theresultant slurry is filtered at 0 C. to separate the crystallineproduct. The filter cake is washed with methanol and air dried at roomtemperature. A substantially quantitative yield of the product of theabove structural representation is obtained.

Example 8 The product of Example 7 is applied to Dacron (ethyleneglycol-terephthalic acid polyester) fiber as follows:

A 10 gms. swatch of Dacron fiber is heated at 205 F. for 1 hour in awater bath containing 300 mls. water and 0.3 gm. of the aboveultra-violet absorber dispersed with 0.3 gm. of nonylphenol condensedwith 12 moles of ethylene oxide. The 0.3 gm. of absorber is dissolvedfirst in 5 mls. of alcohol and the alcohol solution is poured into the300 mls. of water containing theemulsifier. The cloth is removed, rinsedand dried. Cloth so treated shows more stability toward discoloration onexposure to light than untreated cloth.

' Example 9 Preparation of: a

CN 110 o COOCH1C-CH2OH -OC2H5 l The mono-glyceryl ester of cyanoaceticester is first prepared as follows: -94 gms. (1 mole) of cyanoaceticacid (90% pure) 184 gm. glycerol (2 moles) 13.9 gms. of toluenesulfonicacid 200 mls. benzene are refluxed together for 24 hours.

The water liberated during the reaction is removed with a water trap (18mls. (1 mole) of water collected). The catalyst is neutralized withsodium bicarbonate solution. The material is saturated with NaCl andthen extracted with ethyl acetate. The ethyl acetate extract is driedwith anhydrous sodium acetate and the solvent is distilled off, leavingthe light brown oil of 2-ethoxy-l-napht'haldehyde is condensed with theabove glyceryl ester of cyanoacetic acid as in Example 1, employing thesame molar amounts of reactants to give the ultra-violet absorber.

Example The film containing the ultra-violet absorber gave moreprotection against darkening to meat stored behind it than the film freeof absorber upon exposure of each to daylight for several days.

' Example 11 Application of to furniture polish:

A melt is made on a steam bath of:

9 oz. carnauba wax 1.5 pints turpentine 1.75 pints hot water containing2 oz. soap The whole mixture is beaten with a high speed stirrer. Asimilar formulation is made containing 2% based on the weight ofcarnauba wax of the ultra-violet absorbera-cyano-2Tethoxy-l-naphthaleneacrylic acid, ethyl ester.

The formulation containing the ultra-violet a'bsorber when applied tostained and varnished oak gives better protection against discoloration(darkening) by light than the formulation free of absorber.

Example 12 Application of a-cy-ano-2-ethoxy-l-naphthaleneacrylic acid,ethyl ester for the stabilization of coloring matters incorporated inplastics:

10 A lacquer drawdown on Krorne-Kote paper of 2% of Azosol Fast YellowRCA (anthranilic acid 4 sulfophenylmethylpyrazolone, Cr,dicyclohexylamine salt), 2% of u cyano 2 ethoxy-l-naphthaleneacrylicacid ethyl ester in nitrocellulose is made as well as a comparativenitrocellulose lacquer formulation containing 2% Azosol Fast Yellow RCAwithout ultra-violet absorber. After 500 hours fadeometer exposure, thelacquer containing the ultra-violet absorber showed substantially lessfading.

Ethylene glycol di-(a-cyanoacetate) is first prepared according to themethod described in Example 1 of US. Patent 2,426,056 using excesscyanoacetic acid. One molecular equivalent of the crude product isolatedis condensed with 372 g. (2 molecular equivalents) of2-methoxy-l-naphthaldehyde in the presence of 10 gms. piperidine,boiling for 3 hours with 1 liter of ethyl alcohol as solvent. Thealcohol and piperidine are evaporated and the ultra-violet absorber soisolated is used in the crude state in Polylite 8000 (a polyester resinof 30% styrene and glyceral phthalate maleate) as illustrated in thefollowing example.

Example 14 The resin is prepared by adding 1 gm. of a 50% solution ofbenzoyl peroxide in tricresyl phosphate tc Polylite 8000. 0.25 gm. ofthe above ultra-violet absorber is then added to gms. resin. A clearcoating of polyester is made between glass plates spaced A in. apart.The resin is cured by placing the material in an oven at 65 C., thenraising the temperature slowly to 90 C- holding 1 hour, then raisingtemperature to C. and holding 1 hour to complete the cycle. Theresultant sheet is more stable to sunlight than a similar sheet devoid01 the absorber.

Example 15 Preparation of C O O CHQCHQCN OCH Example 16 The compound ofExample 15 is tested for its ultra violet protecting characteristics asin Example 8 am found to be outstanding.

I 1 In the following Examples 17-35, wherein n, R and are as indicatedin Formula III above, the compounds e tested in the indicatedcompositions:

The compounds used in this invention are in general soluble in a greatvariety of solvents, plastics, resins, waxes and the like, and thereforeare particularly adapt- Composition M N HHHHHHHl-u-n- H n-Propyl 1 EthylCyclohexyl. 1 SI-Nonylene Ethyl 2 E1211 1 H y @a Methyl 3 n-Propyl H(])(1311- i Example 2.. 0n Dacron as in Example 8. 0i EIxample l1. 1

0. On Dacron as in Example 8. 0t Example 6. Of Example 2. Of Example 10.

Do. Oi Example 12. On Dacron as in Example 8.

Do. Do.

0i Example 2. Of Example 6.

0t Example 14.

Epou resin.

0! Example 6.

Thefl-nonylene etherot2-hydroxy-l-naphthaldehyde is prepared similarlyas the allyl ether of Example 7 by condensation of l-bromo-nonene 2 withZ-hydroxy-l-naphthaldehyde. 4 The di(eyanoacetate) is preparaed froma,a-diphenylethyleneglycol and cyanoacetic acid similarly as m ample 13for the ethylene glycol der1vat1ve.

The di(cyanoacetate) is prepared from 2,5-dihydroxy pyridine andcyanoacetic acid following the procedure Example 13 for the ethyleneglycol derivative.

The di(cyanoacetate) is prepared from acenaphthyleneglyco landcyanoacetic acid as per procedure of Exvple 13.

As described above, polyoxyllated derivatives may be epared containingfrom one to 100 oxyalkylene groups. ie folowing examples areillustrative.

Example 36 The compound of Example 23 is polyoxyalkylated with iyleneoxide by adding to 1 mole thereof 1.3% by right of pot'asium hydroxideand then moles of eth- :ne oxide in an autoclave at 80 C.

Example 37 Example 36 is repeated by employing moles of eth ene oxide toyield a product containing 35 oxyethyl oups.

Example 38 Example 36 is repeated using 10 moles of propylene .ide inlieu of ethylene oxide. The resultant product conins 10 oxypropylgroups.

Example 39 Example 38 is repeated and then 10 moles of ethylene .ide arefurther added to give a product containing 10 ;ypropyl groups and 9oxyethyl groups and a terminal 'droxyethyl group.

Example 40 The product of Example 36 is dispersed in water (5 100 water)and used to treat paper and cotton.

Example 41 able for the stabilization of a great variety of differenttypes of organic materials. The'non-oxyalkylated products vare'insolublein water. Those c-ompounds which contain smaller amounts of oxyalkylgroups, that is, up to about 4 to 6 groups per molecule, are in generalsoluble in the more polar organic solvents and fairly readilydispersible in water. The compounds containing larger amounts ofalkylene oxide, that is, above about 6 moles per mole of reactivehydrogen containing compound, range from soluble to extremely soluble inwater in the case of oxyethylene groups, the solubility increasing asthe number of oxyalkyl groups are increased.

The amount of stabilizer to be incorporated is not particularly criticalexcept that sufiicient should be present to effect the desired degree ofstabilization, and no more should be employed than is necessary toobtain this result. In general, between 0.1% and 10% based on the solidscontent of the organic material may be used, and preferably betweenabout ().S% to about 2% As exemplified above, the ultra-violet absorbersemployed with this invention can be used not only to stabilize clearfilms, plastics and the like, but they may be employed in opaque,semi-opaque or translucent materials, the surface of which issusceptible to degradation by ultra-violet light. Among such differenttypes of materials, most of which have'been exemplified, arefoamed'plastics, opaque'filmsandcoatings, opaque papers, translucent andopaque fibers, transparent and opaque colored plastics, fluorescentpigments, polishes, creams, lotions and the like whether opaque, clear,or translucent. The compounds employed in this invention giveoutstanding protection to paint, enamel and varnish films agaianstfading of pigments and dyes contained therein.

Of particularly outstanding significanceis the use of the compoundsherein described in combination with high molecular weight polymers offormaldehyde such as Delrin. The incorporation of from 1 to 5% of thecompounds described herein in such polymers yields an outstandingimprovement in the stability of the polymer. The compounds may beincorporated in the finished polymer or preferably in the polymerizingmass. Other stabilizers such as the benzothiazoles and the benzophenonescannot be used in this manner since they cause depolymerization.

Another outstanding use of the compounds lies in the employment thereofin the transparent backings of pressure-sensitive tapes whereby theadhesive is protected against the degradative eflects of the environmentand particularly of the active radiations. In such use, the compoundsmay be added to the plastic backing material in the manufacture thereofor impregnated or coated therer on or therein.-

Other variations in and modifications of the described processes whichwill be obvious to those skilled in the art can be made in thisinvention without departing from the scope or spirit thereof.

We claim:

1. A method for protecting organic carrier material against thedegradative effects of ultra-violet radiation which comprisesincorporating with said organic carrier from about 0.05% to about 2% byweight based on the weight of the organic material, as an absorber forultraviolet radiation, an essentially colorless compound capable ofabsorbing ultra-violet light in the range of 250- 400 millimicronshaving the formula COOR2 l to 2, and when n is 1, R is a radicalselected from the group consisting of alkyl, hydroxyalkyl, haloalkyl,cyanoalkyl, alkoxyalkyl, hydroxy alkoxyalkyl, carbalkoxyalkyl, alkenyl,aryl, substituted aryl, and hetero radicals, and when n. is 2, R is aradical selected from the group consisting of alkylene, substitutedalkylene, arylene, substituted arylene, and bi-substituted heterocyclicradicals.

2. A method as defined in claim 1 wherein n is 1, and R and R are ethyl.

3. A method as defined in claim 1 wherein n is 1, and R and R aremethyl.

4. A method as defined in claim 1 wherein n is 1, R is alkenyl and R isalkyl.

5. A method as defined in claim 1 wherein n is 1, R is alkyl and R isheterocyclic.

6. A method as defined in claim 1 wherein n is 2, R is alkyl and R isalkylene.

7. A method as defined in claim 1 wherein n is 2, R is alkenyl and R isalkylene.

8. A method as defined in claim 1 wherein n is 2, R, is alkyl and R isarylene.

9. A method as defined in claim 10 wherein said organic carrier isnitrocellulose.

10. A method as defined in claim 1 wherein the absorber is present in anamount by weight of about 0.5% based on the weight of the organiccarrier.

11. A method as defined in claim 10 wherein said organic carrier is acellulose ester plastic material.

12. A method as defined in claim 10 wherein said organic carrier ispolyethylene.

13. A method as defined in claim 10 wherein said or ganic carrier is apolyester resin.

14. A method as defined in claim 10 wherein said or ganic carrier is anatural wax.

References Cited FOREIGN PATENTS 588,864 12/1959 Canada.

ALLAN LIEBERMAN, Primary Examiner.

